BALANCED CHARGE-RECYCLING REPEATER LINK

• US 20170093403A1
• Filed: 09/29/2015
• Published: 03/30/2017
• Est. Priority Date: 09/29/2015
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Wilson, John Michael, Poulton, John W., Fojtik, Matthew Rudolph, Gray, Carl Thomas
• Granted Patent: US 9,954,527 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03K 19/018528 with at least one differential stage

Abstract

A balanced, charge-recycling repeater link is disclosed. The link includes a first set of segments operating in a first voltage domain and a second set of segments operating in a second voltage domain. The link is configured to transmit a first signal over at least one segment in the first set of segments and at least one other segment in the second set of segments. Each segment of the link includes at least one active circuit element configured to charge or discharge one or more corresponding interconnects within the link and a level shifter configured to shift the level of a signal on a last interconnect of the segment from the first voltage domain to the second voltage domain or the second voltage domain to the first voltage domain.

Claims

1. A balanced, charge-recycling repeater link, comprising:

a first set of segments operating in a first voltage domain; and

a second set of segments operating in a second voltage domain,

wherein the link is configured to transmit a first signal over at least one segment in the first set of segments and at least one other segment in the second set of segments, and

wherein each segment of the link includes;

at least one active circuit element configured to charge or discharge one or more corresponding interconnects within the link, and

a level shifter configured to shift the level of a signal from the first voltage domain to the second voltage domain or the second voltage domain to the first voltage domain.

2. The balanced, charge-recycling repeater link of claim 1, wherein the first voltage domain is characterized by a high logic state represented by a high supply voltage and a low logic state represented by a mid-range supply voltage, and wherein the second voltage domain is characterized by a high logic state represented by the mid-range supply voltage and a low logic state represented by a low supply voltage.

3. The balanced, charge-recycling repeater link of claim 2, wherein the mid-range supply voltage is a potential halfway between a potential of the high supply voltage and a potential of the low supply voltage.

4. The balanced, charge-recycling repeater link of claim 1, wherein each active circuit element in the at least one active circuit element comprises a CMOS inverter.

5. The balanced, charge-recycling repeater link of claim 1, wherein the at least one active circuit element comprises a plurality of inverters configured to charge or discharge a plurality of corresponding interconnects within the segment.

6. The balanced, charge-recycling repeater link of claim 1, wherein the level shifters comprise clocked level shifters, where each clocked level shifter includes a pair of sense amplifier circuits and a pair of slave circuits to decouple the sense amplifier circuits from an output signal.

7. The balanced, charge-recycling repeater link of claim 6, wherein the level shifters included in the first set of segments are configured to shift the level of the signal from the first voltage domain to the second voltage domain, and wherein the level shifters included in the second set of segments are configured to shift the level of the signal from the second voltage domain to the first voltage domain.

8. The balanced, charge-recycling repeater link of claim 6, wherein the sense amplifier circuits are supplied by a full-swing voltage domain characterized by a high supply voltage and a low supply voltage.

9. The balanced, charge-recycling repeater link of claim 1, wherein the level shifters comprise at least one of a current mirror level shifter, a cross-coupled pair level shifter, and a capacitively-coupled level shifter.

10. The balanced, charge-recycling repeater link of claim 1, wherein a first segment at the beginning of the balanced, charge-recycling repeater link and a second segment at the end of the balanced, charge-recycling repeater link include half a number of active circuit elements as each of the other segments in the first set of segments and the second set of segments.

11. An integrated circuit, the integrated circuit comprising:

a first logic block; and

a second logic block coupled to the first logic block via a balanced, charge-recycling repeater link that includes;

a first set of segments operating in a first voltage domain, and

a second set of segments operating in a second voltage domain,

wherein the link is configured to transmit a first signal over at least one segment in the first set of segments and at least one other segment in the second set of segments, and

wherein each segment of the link includes;

at least one active circuit element configured to charge or discharge one or more corresponding interconnects within the link, and

a level shifter configured to shift the level of a signal from the first voltage domain to the second voltage domain or the second voltage domain to the first voltage domain.

12. The integrated circuit of claim 11, wherein the first voltage domain is characterized by a high logic state represented by a high supply voltage and a low logic state represented by a mid-range supply voltage, and wherein the second voltage domain is characterized by a high logic state represented by the mid-range supply voltage and a low logic state represented by a low supply voltage.

13. The integrated circuit of claim 12, wherein the mid-range supply voltage is a potential halfway between a potential of the high supply voltage and a potential of the low supply voltage.

14. The integrated circuit of claim 11, wherein each active circuit element in the at least one active circuit element comprises a CMOS inverter.

15. The integrated circuit of claim 11, wherein the at least one active circuit element comprises a plurality of inverters configured to charge or discharge a plurality of corresponding interconnects within the segment.

16. The integrated circuit of claim 11, wherein the level shifters comprise clocked level shifters, where each clocked level shifter includes a pair of sense amplifier circuits and a pair of slave circuits to decouple the sense amplifier circuits from an output signal.

17. The integrated circuit of claim 16, wherein the level shifters included in the first set of segments are configured to shift the level of the signal from the first voltage domain to the second voltage domain, and wherein the level shifters included in the second set of segments are configured to shift the level of the signal from the second voltage domain to the first voltage domain.

18. The integrated circuit of claim 11, wherein the level shifters comprise at least one of a current mirror level shifter, a cross-coupled pair level shifter, and a capacitively-coupled level shifter.

19. The integrated circuit of claim 11, wherein the first logic block is coupled to the second logic block via a plurality of balanced, charge-recycling repeater links operating in parallel.

20. A system, comprising:

a memory; and

a processor including;

a first logic block; and

a second logic block coupled to the first logic block via a balanced, charge-recycling repeater link that includes;

a first set of segments operating in a first voltage domain, and

a second set of segments operating in a second voltage domain,

wherein the link is configured to transmit a first signal over at least one segment in the first set of segments and at least one other segment in the second set of segments, and

wherein each segment of the link includes;

at least one active circuit element configured to charge or discharge one or more corresponding interconnects within the link, and

a level shifter configured to shift the level of a signal from the first voltage domain to the second voltage domain or the second voltage domain to the first voltage domain.